Sources fetched 13 November 2026. PawLine editorial team. Not professionally reviewed.
Fish-feeding education, not veterinary advice. Contact a fish-experienced veterinarian promptly for illness, injury, appetite change or concern. Do not wait for this note or an app answer. No feeding, fasting, treatment or safe waiting interval is supplied.
Keep the source beside the number
RSPCA UK and SPCA education describe little-and-often routines; PetMD gives once or twice daily depending on species. Merck distinguishes some carnivorous fish that eat large meals. These are not one shared dataset. Do not average the numbers, choose the smallest workload or apply an exception because a fish looks similar.
RSPCA PetMD MSDVeterinaryManual AVMA MerckVeterinaryManual SPCAKidsEducation
The evidence has limits
Merck warns that detailed nutritional needs are known for only a small fraction of fish species. Similar-looking but unrelated animals need not have interchangeable diets. A confident table cannot erase that uncertainty. This site has no species selector that turns a name into a feeding prescription.
RSPCA PetMD MSDVeterinaryManual AVMA MerckVeterinaryManual SPCAKidsEducation
Frequency is not quantity
How often is not how much. The sources also use time-based portions and body-weight descriptions in different contexts. We convert none into pinches, pellets, grams or percentages. No weighing, new measurement, timed feeding trial or equipment change is requested for the note.
RSPCA PetMD MSDVeterinaryManual AVMA MerckVeterinaryManual SPCAKidsEducation
Ask about the actual setting
Ask the fish veterinarian what food, amount, timing and method fit the real fish and circumstances. Use existing broad information rather than an improvised test. This page cannot decide a change or establish that an older instruction still applies.
RSPCA PetMD MSDVeterinaryManual AVMA MerckVeterinaryManual SPCAKidsEducation
Sources and limits
RSPCA:Whattofeedyourpetfish,undated
PetMD:WhatDoFishEat?,displayupdated31March2026
MSDVeterinaryManual:ProvidingaHomeforFish,fullreviewFeb2020updatedApr2026
AVMA:Elevenquestionstoaskyourveterinarianaboutyourpetfish,undated
MerckVeterinaryManual:NutritionalDiseasesofFish,fullreviewMay2022updatedJun2026